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Abstract: In this work, a facile method for fabricating fibers with micro- and nano-porous structure by electrospinning a ternary system of nonsolvent/solvent/poly(l-lactic acid) is presented. Poly(l-lactic acid) (PLLA) was dissolved in a mixture of dichloromethane (solvent) and butanol (nonsolvent) with a certain ratio. During the electrospinning, the evaporation of solvent and nonsolvent would take the composition of polymer fluid jet to enter the two phase region of the ternary phase diagram, since the solvent is more volatile than the nonsolvent. Thus the jet yielded to different phase separated structures, and further evaporation of the residual nonsolvent would lead to porous fibers. [Copyright &y& Elsevier]

Differential susceptibility to diabetic nephropathy has been observed in humans, but it has not been well defined in inbred strains of mice. The present studies characterized the severity of diabetic nephropathy in six inbred mouse strains including C57BL/6J, DBA/2J, FVB/NJ, MRL/MpJ, A/J, and KK/HlJ mice. Diabetes mellitus was induced using low-dose streptozotocin injection. Progression of renal injury was evaluated by serial measurements of urinary albumin excretion, glomerular filtration rate (GFR), and terminal assessment of renal morphology over 25 weeks. Despite comparable levels of hyperglycemia, urinary albumin excretion and renal histopathological changes were dramatically different among strains. DBA/2J and KK/HlJ mice developed significantly more albuminuria than C57BL/6J, MRL/MpJ, and A/J mice. Severe glomerular mesangial expansion, nodular glomerulosclerosis, and arteriolar hyalinosis were observed in diabetic DBA/2J and KK/HlJ mice. Glomerular hyperfiltration was observed in all diabetic strains studied except A/J. The significant decline in GFR was not evident over the 25-week period of study, but diabetic DBA/2J mice exhibited a tendency for GFR to decline. Taken together, these results indicate that differential susceptibility to diabetic nephropathy exists in inbred mice. DBA/2J and KK/HlJ mice are more prone to diabetic nephropathy, whereas the most widely used C57BL/6J mice are relatively resistant to development of diabetic nephropathy. [ABSTRACT FROM AUTHOR]

Utility of endogenous creatinine clearance as a measure of renal function in mice. Background. The use of endogenous plasma creatinine levels and creatinine clearance as a tool to evaluate renal function in mice has come under scrutiny as prior studies have reported that the Jaffé alkaline picrate method grossly overestimates true plasma creatinine in mice. As members of the NIDDK Animal Models of Diabetic Complications Consortium (AMDCC), we evaluated the performance and feasibility of an alternative high-performance liquid chromatography (HPLC)-based method for standard determination of plasma creatinine and creatinine clearance in mice. Our purpose was to develop a simple method that provides a reliable, reproducible, and sensitive assay for small volumes (<25 μL) of mouse plasma and sera. Methods. We compared creatinine clearance measured by HPLC with the Jaffé method and HPLC creatinine clearance with inulin clearance [fluoroscein isothiocyanate (FITC) inulin in an osmotic pump implanted in mouse] in C57BL/6J mice. Different groups of mice underwent either one of two protocols. Protocol A included dietary intervention with normal, low salt plus enalapril, or high salt. Protocol B induced diabetes using streptozotocin. Results. First, mean plasma creatinine levels were significantly lower ( P < 0.0001) by HPLC (0.128 ± 0.026 mg/dL) vs. Jaffé (0.4 ± 0.12 mg/dL) for mice on a normal diet. Urine creatinine concentrations measured by HPLC were 10% lower than by Jaffé ( P < 0.01). Second, mean creatinine clearance by HPLC for mice on a normal diet was 255 ± 68 μL/min. Mice on low salt diet plus enalapril had reduced creatinine clearance (72.8 ± 24.2 μL/min) while mice on high salt diet had an elevated creatinine clearance (355 ± 105 μL/min). Third, diabetic mice (19 to 24 weeks of diabetes) exhibited hyperfiltration as creatinine clearance was 524 ± 214 μL/min whereas nondiabetic age/gender-matched mice showed a mean creatinine clearance of 206 ± 41 μL/min. Finally, significant correlation was demonstrated for creatinine clearance by HPLC vs. inulin clearance ( R= 0.643; P < 0.001). Conclusion. HPLC is highly accurate, much more sensitive and specific than the Jaffé method for plasma creatinine measurements in mice. Creatinine clearance in mice measured by HPLC reflects changes in renal function induced by diet and diabetes. [ABSTRACT FROM AUTHOR]

Therapeutic use of cyclooxygenase-inhibiting (COX-inhibiting) nonsteroidal antiinflammatory drugs (NSAIDs) is often complicated by renal side effects including hypertension and edema. The present studies were undertaken to elucidate the roles of COX1 and COX2 in regulating blood pressure and renal function. COX2 inhibitors or gene knockout dramatically augment the pressor effect of angiotensin II (Ang II). Unexpectedly, after a brief increase, the pressor effect of Ang II was abolished by COX1 deficiency (either inhibitor or knockout). Ang II infusion also reduced medullary blood flow in COX2-deficient but not in control or COX1-deficient animals, suggesting synthesis of COX2-dependent vasodilators in the renal medulla. Consistent with this, Ang II failed to stimulate renal medullary prostaglandin E(2) and prostaglandin I(2) production in COX2-deficient animals. Ang II infusion normally promotes natriuresis and diuresis, but COX2 deficiency blocked this effect. Thus, COX1 and COX2 exert opposite effects on systemic blood pressure and renal function. COX2 inhibitors reduce renal medullary blood flow, decrease urine flow, and enhance the pressor effect of Ang II. In contrast, the pressor effect of Ang II is blunted by COX1 inhibition. These results suggest that, rather than having similar cardiovascular effects, the activities of COX1 and COX2 are functionally antagonistic. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the role and expression of cyclic adenosine monophosphate-dependent protein kinase in regulating electrogenic ion transport in rabbit cortical collecting ducts. Materials and methods used in the study; Results and discussion.

The use of creatinine to estimate glomerular filtration rate in patients is prone to well-described artifacts that impact its interpretation. Eisner et al. now show that the impact of creatinine secretion on creatinine clearance is even larger in mice than in humans, raising questions regarding the utility of creatinine for measuring glomerular filtration rate in mice. [ABSTRACT FROM AUTHOR]

Take Maimendong Decoction (MMDD), one of the Chinese classic herbal formulas, as an object to evaluate the chemical consistency between traditional decoction and mixed decoction. The ultra-performance liquid chromatography coupled to quadrupole with time-of-flight mass spectrometry-based chemical profiling approach has been utilized. A total of 48 major peaks are detected from these two decoctions under the present chromatographic and mass spectrometry conditions. The results of negative ion mode show nine significant inconsistencies. Liquiritin, ginsenoside Ro and ginsenoside Rg5/Rk1 are detected with higher intensity in traditional preparation sample than the mixed decoction, while licoisoflavone A is higher in mixed decoction samples than the traditional one. The mechanisms involved in the chemical changes were assumed to be anti-inflammation, anti-oxidative stress and so on, suggesting these two different preparation approaches of MMDD may lead to a possibility of discrepant clinical outcomes. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (types 1 and 2) is the leading cause of glomerular disease and end-stage renal disease in most developed countries, with estimates that one-third of people living with diabetes will develop diabetic kidney disease (DKD). The current standard of care medications slow but do not arrest progression of kidney disease, and therefore, therapy for DKD is a highly unmet medical need for patients. To discover and test novel and durable new therapies, it is necessary to develop animal models of human DKD, which authentically recapitulate the human disease state and provide translatable efficacy to human patients. Here, we review selected mouse models of human DKD, which demonstrate many of the features of type 2 human DKD. [ABSTRACT FROM AUTHOR]

Lightweight carbon fiber/carbon composites (CFC) are widely used in solar silicon furnace, semiconductor long crystal furnace and other high-temperature equipment due to its superior low thermal conductivity, low expansion coefficient, high purity, good mechanical properties, and high temperature resistance. In this paper, the lightweight chopped CFC was prepared by the method of liquid phase dispersion of chopped carbon fibers-vacuum filtration-curing molding-high temperature carbonization and graphitization. The thermal conductivity of lightweight chopped CFC with different densities (0.12, 0.16 and 0.18 g/cm3) was studied, and the thermal conductivity of lightweight chopped CFC at high temperature was also studied. The results show that the thermal conductivity (1000 °C) of the chopped CFC gradually increases with the increasing density from 0.179 W/(mK) (0.12 g/cm3) to 0.190 W/(mK) (0.16 g/cm3), 0.282 W/(mK) (0.18 g/cm3), indicating that with the increasing density, the thermal conduction path of the carbon fiber increases, the thermal conductivity of the CFC material increases, and then the thermal insulation performance decreases. In addition, with the increasing temperature, the phonon vibration increases, the thermal conductivity of the CFC material also increases, and then the thermal insulation performance decreases. [ABSTRACT FROM AUTHOR]

Purpose: Numerous studies have tried to combine transarterial chemoembolization (TACE) or hepatic arterial infusion chemotherapy (HAIC) with radiotherapy (RT) for the treatment of hepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT). However, the efficacy of TACE or HAIC combined with RT versus TACE or HAIC alone remains controversial. Thus, we performed a meta-analysis to compare the efficacy and safety of intra-arterial chemoembolization combined with RT versus intra-arterial chemoembolization alone for the treatment of HCC patients with PVTT.Methods: PubMed, Embase, and Cochrane Library databases were systematically searched for eligible studies. Two authors independently reviewed the abstracts, extracted relevant data and rated the quality of studies. The major end points were objective response rate (ORR), overall survival (OS), and adverse events.Results: Eight studies with a total of 1,760 patients were included in this meta-analysis. The pooled results showed that intra-arterial chemoembolization combined with RT significantly improved ORR of PVTT (OR, 4.22; 95% CI, 3.07-5.80; P<0.001) and OS (HR, 0.69; 95% CI, 0.57-0.83; P=0.001), but did not affect ORR of primary liver tumor (OR, 1.37; 95% CI, 0.67-2.79; P=0.390). The incidence of grade 3 or 4 leukopenia (OR, 5.80; 95% CI, 2.478-13.56; P<0.001) and thrombocytopenia (OR, 3.77; 95% CI, 1.06-13.43; P=0.041) was higher in the intra-arterial chemoembolization plus RT group than in the intra-arterial chemoembolization group.Conclusion: Combination therapy of intra-arterial chemoembolization and RT for HCC patients with PVTT could bring higher ORR of PVTT and better survival benefits. This combination therapy was also associated with a significantly increased risk of adverse events. However, they were mostly mild to moderate and successfully treated with conservative treatment. [ABSTRACT FROM AUTHOR]

Chrysin (CH) is an important natural plant flavonoid and possesses diverse pharmacological activities. Our present investigations aimed to assess the neuroprotection of CH against diabetes-associated cognitive decline (DACD) in a rat model of diabetes and exploring its potential mechanism. Diabetic model was induced by intraperitoneal injection of streptozotocin. Then, they were treated with vehicle or CH by doses of 30 and 100 mg/kg for 26 days. Learning and memory function was evaluated by Morris water maze test. The oxidative indicators [malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH)], NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-3 were measured in cerebral cortex and hippocampus using corresponding commercial kits. The diabetic rats showed marked reductions in body weight, percentage of time spent in target quadrant and number of times of crossing platform, coupled with increases in plasma glucose levels, escape latency, mean path length and oxidative stress (increased MDA level and decreased CAT and SOD as well as reduced GSH), NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-3 in cerebral cortex and hippocampus. Moreover, CH supplement dramatically reversed the corresponding behavioral, biochemical and molecular alterations in diabetes. The alterations of swimming speed among different groups were not observed after CH adminstration. In conclusion, our current work discloses that CH remarkably alleviates DACD and suggests that oxidative stress, inflammation and apoptotic cascades are linked with diabetes-associated cognitive deficits. These findings point toward the therapeutic potential of CH in DACD. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have shown that Prostaglandin E2 (PGE2) inhibits glucose-stimulated insulin secretion. However, the role of cyclooxygenase (COX)-1 vs. COX-2 derived PGE2 production in glucose-stimulated insulin secretion remains poorly understood. Here we investigated the expression of COX-1 and COX-2 in pancreatic islets and the effect of selective inhibition of COX-1 and COX-2 on glucose-stimulated insulin secretion using C57BL/6 (B6) mice. Although immunofluorescence histochemistry showed the constitutive expression of both COX-1 and COX-2 in B6 mouse pancreatic islets, insulin secretion and hyperglycemia after glucose loading were ameliorated in B6 mice treated with selective COX-2 inhibitor (SC58236) for 18 weeks. Interestingly, incubation with selective COX-2 inhibitor for 24h led to a reduction in PGE2 production in pancreatic islets isolated from B6 mice. In addition, selective COX-2 inhibition enhanced insulin secretion from the isolated islets. These results collectively suggest that selective inhibition of COX-2 enhances glucose-stimulated insulin secretion through a reduction in PGE2 production in pancreatic islets. [Copyright &y& Elsevier]

Clinical use of prostaglandin synthase-inhibiting NSAIDs is associated with the development of hypertension; however, the cardiovascular effects of antagonists for individual prostaglandin receptors remain uncharacterized. The present studies were aimed at elucidating the role of prostaglandin E2 (PGE2) E-prostanoid receptor subtype 1 (EP1) in regulating blood pressure. Oral administration of the EP1 receptor antagonist SC51322 reduced blood pressure in spontaneously hypertensive rats. To define whether this antihypertensive effect was caused by EP1 receptor inhibition, an EP1-null mouse was generated using a "hit-and-run" strategy that disrupted the gene encoding EP1 but spared expression of protein kinase N (PKN) encoded at the EP1 locus on the antiparallel DNA strand. Selective genetic disruption of the EP1 receptor blunted the acute pressor response to Ang II and reduced chronic Ang II-driven hypertension. SC51322 blunted the constricting effect of Ang II on in vitro-perfused preglomerular renal arterioles and mesenteric arteriolar rings. Similarly, the pressor response to EP1-selective agonists sulprostone and 17-phenyltrinor PGE2 were blunted by SC51322 and in EP1-null mice. These data support the possibility of targeting the EP1 receptor for antihypertensive therapy. [ABSTRACT FROM AUTHOR]

Macula densa (MD) cells express COX-2 and COX-2-derived PGs appear to signal the release of renin from the renal juxtaglomerular apparatus, especially during volume depletion. However, the synthetic machinery and identity of the specific prostanoid released from intact MD cells remains uncertain. In the present studies, a novel biosensor tool was engineered to directly determine whether MD cells release PGE2 in response to low luminal NaCl concentration ([NaCl]L). HEK293 cells were transfected with the Ca2+-coupled E-prostanoid receptor EP1 (HEK/EP1) and loaded with fura-2. HEK/EP1 cells produced a significant elevation in intracellular [Ca2+] ([Ca2+]i) by 29.6 +/- 12.8 nM (n = 6) when positioned at the basolateral surface of isolated perfused MD cells and [NaCl]L was reduced from 150 mM to zero. HEK/EP1 [Ca2+]i responses were observed mainly in preparations from rabbits on a low-salt diet and were completely inhibited by either a selective COX-2 inhibitor or an EP1 antagonist, and also by 100 microM luminal furosemide. Also, 20-mM graduated reductions in [NaCl]L between 80 and 0 mM caused step-by-step increases in HEK/EP1 [Ca2+]i. Low-salt diet greatly increased the expression of both COX-2 and microsome-associated PGE synthase (mPGES) in the MD. These studies provide the first direct evidence that intact MD cells synthesize and release PGE2 during reduced luminal salt content and suggest that this response is important in the control of renin release and renal vascular resistance during salt deprivation. [ABSTRACT FROM AUTHOR]